turbo spool up times and low dw rev power

[damo_mk3]

now i've been looking in to this and it seams to me that big ish bhp the tuby don't spool up till 3500 to 4000 rpm but when u have a car with limint of 6500 ish your not gettin much on boost time

Can anything to be done to help the lower rev power

[Adam W]

Bigger engine, smaller turbo, or nitrous are about the only ways you can bring the power on quicker! I have a Garrett T67, I don't think I'd want to go any bigger on a Mk3 with the standard rev limit unless you were building it purely for drag racing. It makes more power than I know what to do with, even at very low boost, from 2500rpm you can hear a faint whistle from it as it starts to spin, from 3000 you have reasonable power, building up smoothly to 4000rpm where all hell breaks loose and you scorch off down the road screaming your head off with your **** chewing a hole through the seat ;)

It can be a bit tricky when overtaking, you want to be right in the powerband to nip past someone and if they're doing 45 or 50mph you have to drop it down to second gear to get full boost, which can mean a whole lotta wheelspin in a gear that low. If you leave it in third you creep up on them slowly until you hit 60mph and *then* you really take off and whiz past em. You have the same dilemma sometimes coming out of really tight corners - third gear with no boost or second gear with full boost and no traction :D

Even though the powerband has gotten a fair bit smaller with the big turbo, there is no doubt that the car is faster and a whole lot more fun to drive than with my old hybrid turbo on. I've managed one run at 18psi now and it was just utterly surreal, unbelieveably fast. It pulled through fourth gear harder than a standard or BPU car will pull through 2nd.

In short, if you want big power on a turbo car with a small engine you will have to deal with it, but it's not a big deal really :D

[damo_mk3]

well thats that then but i don't think the turbo i need will be as big as yours so will have a bigger power band but still looking at around 16-20psi MAX tho :)

i beleave you can run a stupid amount of boost on yours tho like 30psi or so :notworthy

if i could do a mid 11 sec 1/4 mile that would be fine but i need to keep my car reliable (engine) the gear box goes or the drive shaft i don't mind as much as the engine. if that was to go i whould hang mi self. im on my 3rd try and engine biulding (with stock parts) and its doing me in, having to do it every 3 months. :crybaby:

i use my car for to many hard driving things must take it easy for a little bit. no more 1/4 miles and less drfting for me over the next 12 months

damo

[Anh]

well thats that then but i don't think the turbo i need will be as big as yours so will have a bigger power band but still looking at around 16-20psi MAX tho :)

if i could do a mid 11 sec 1/4 mile that would be fine but i need to keep my car reliable (engine) the gear box goes or the drive shaft i don't mind as much as the engine. if that was to go i whould hang mi self. im on my 3rd try and engine biulding (with stock parts) and its doing me in, having to do it every 3 months. :crybaby:

i use my car for to many hard driving things must take it easy for a little bit. no more 1/4 miles and less drfting for me over the next 12 months

damo

Don't worry too much about power bands, really! Remember than torque thru the revs are governed by engine size. With 3 litres to play with, the weight of the car per litre is far better in a Supra than say any Cosworth or Skyline. Check out how gutless the latter 2 cars are on the dyno before 3000 - 4000 revs, then divide it by the weight of the car!

Sure, larger turbos will make less power at low revs than the standard CT26 but the powerband won't ruin your 1/4 mile time. Supra's are just a pain in the a*** because of their standard independent suspension set up, I'd worry about that more than what power you make at 1800 rpm. :)